1. Field of the Invention
The present invention relates to a channel server, a channel prediction server, a terminal, and a method for a fast channel switching.
2. Description of the Related Art
An Internet Protocol Television (IPTV) service denotes a service of combining various communication broadcastings provided based on an IP network. In real-time broadcasting constituting a basis of the IPTV service, a channel switching speed becomes a very important factor in an aspect of user satisfaction. In the case of the real-time broadcasting provided using a conventional analog broadcasting network, the channel switching speed is less than or equal to one second. On the other hand, in the case of the real-time broadcasting service provided using an IPTV network, the channel switching speed is about a few seconds. Accordingly, the channel switching speed needs to be enhanced in order to provide an advanced IPTV service.
In a multicast-based IPTV network, factors affecting the channel switching speed may include, for example, an Internet Group Management Protocol (IGMP) transfer time from a terminal to a router, a multicast stream transfer time from the router to the terminal, a stream buffering time, a Program Identifier (PID) detection time, a time spent due to a Group of Picture (GOP) structure to retrieve an Independent-frame (I-frame), a stream decoding time, a screen output time, and the like. Among the above factors, the IGMP transfer time from the terminal to the router, the multicast stream transfer time from the router to the terminal, the stream decoding time, the screen output time, and the like correspond to basic factors and thus may have a low enhancement probability with respect to the channel switching speed. On the other hand, the stream buffering time, the PID detection time, and the time spent due to the GOP structure to retrieve the I-frame may have a relatively high enhancement probability with respect to the channel switching speed.